Early life stress encodes lifelong susceptibility to stress through long-lasting transcriptional programming in a brain reward region implicated in mood and depression, according to a study conducted at the Icahn School of Medicine at Mount Sinai and published June 15 in the journal Science. The Mount Sinai study focuses on epigenetics, the study of changes in the action of genes caused not by changes in DNA code we inherit from our parents, but instead by molecules that regulate when, where, and to what degree our genetic material is activated. Such regulation derives, in part, from the function of transcription factors – specialized proteins that bind to specific DNA sequences in our genes and either encourage or shut down the expression of a given gene. Previous studies in humans and animals have suggested that early life stress increases the risk for depression and other psychiatric syndromes, but the neurobiology linking the two has remained elusive until now.